scholarly journals Survey On The Incidence And Severity Of Common Scab Of Potato In Bangladesh

2013 ◽  
Vol 39 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Najmun Naher ◽  
Mohammad Hossain ◽  
MA Bashar
Keyword(s):  
Disease Severity ◽  
Common Scab ◽  
Disease Incidence ◽  
Commercial Variety ◽  
Streptomyces Sp ◽  
Cropping Season ◽  
Potato Common Scab ◽  
Made In

A survey on the incidence and severity of common scab (Streptomyces sp.) of potato was made in the major potato growing districts of Bangladesh during the cropping season of 2007-2008. A total of 150 fields was surveyed for collection of potato common scab infected samples. It was observed that there was a lot of variation in disease severity and its incidence in different districts of Bangladesh. Highest per cent scab incidence (71.41 %) was recorded in Kahalo Upazila (Bogra) and lowest (13.79 %) in Pirgacha Upazila (Rangpur). Disease incidence also varied among the tested varieties namely, Cardinal, Diamant, Granola, Binella and Raja. Highest incidence was observed in Cardinal (54.08 %) followed by Binella (50.71 %) and it was lowest in Raja (3.07 %). Cardinal and Binella were found to be highly susceptible and Raja was resistant to common scab disease. Diamant, the commercial variety showed medium susceptible reaction to the disease. J. Asiat. Soc. Bangladesh, Sci. 39(1): 35-41, June 2013 DOI: http://dx.doi.org/10.3329/jasbs.v39i1.16031

scholarly journals Study on Medium Ingredient Composition for Enhancing Biomass Productionand Anti-potato Common Scab Activity of Streptomyces sp. A020645 as a BCA Candidate

2005 ◽  
Vol 11 (1) ◽  
pp. 66-71 ◽  
Author(s):  
Hyang-Burm Lee ◽  
Hyo-Young Roh ◽  
Dong-Jin Park ◽  
So-Keum Lee ◽  
Young-wan Ko ◽  
...  
Keyword(s):  
Common Scab ◽  
Streptomyces Sp ◽  
Potato Common Scab ◽  
Ingredient Composition

scholarly journals Repeated Applications of a Nonpathogenic Streptomyces Strain Enhance Development of Suppressiveness to Potato Common Scab

Plant Disease ◽  
2017 ◽  
Vol 101 (1) ◽  
pp. 224-232 ◽  
Author(s):  
Lea H. Hiltunen ◽  
Jani Kelloniemi ◽  
Jari P. T. Valkonen
Keyword(s):  
Common Scab ◽  
Disease Incidence ◽  
Potato Cultivar ◽  
Disease Suppression ◽  
Streptomyces Strain ◽  
Streptomyces Spp ◽  
Potato Common Scab ◽  
Repeated Applications ◽  
Disease Pressure

Potato common scab caused by several Streptomyces spp. is an important disease with no effective methods of control. Suppressiveness against common scab can develop in soil as a result of long-term potato monoculture and has been associated with nonpathogenic Streptomyces spp. To determine whether the development of scab suppressiveness could be enhanced, the effect of repeated applications of an antagonistic Streptomyces strain on common scab was investigated in a long-term field trial over 5 years. Streptomyces strain 272 applied annually at planting consistently suppressed development of common scab symptoms. On scab-susceptible potato cultivar Bintje, strain 272 reduced disease severity, on average, by 43%; whereas, on the scab-tolerant Nicola, the strain reduced both disease incidence and severity by 43 and 59%, respectively. Regardless of disease pressure, the combined use of strain 272 and the tolerant cultivar reduced the scab coverage to a negligible level. After a single application of strain 272, efficient disease suppression did not persist in the soil to the following growing season. However, when strain 272 was applied in three or more consecutive years, the soil remained suppressive to scab for at least 2 years beyond the last application, suggesting that, with repeated applications, it may be possible to enhance development of scab suppression in soil.

scholarly journals A Novel Streptomyces sp. Strain PBSH9 for Controlling Potato Common Scab Caused by Streptomyces galilaeus

Plant Disease ◽  
2020 ◽  
Vol 104 (7) ◽  
pp. 1986-1993
Author(s):  
Xiao-yu Zhang ◽  
Chi Li ◽  
Jian-jun Hao ◽  
Yu-chen Li ◽  
De-zhou Li ◽  
...  
Keyword(s):  
Common Scab ◽  
Inhibition Zone ◽  
Field Trials ◽  
Potential Candidate ◽  
Streptomyces Sp ◽  
Soilborne Disease ◽  
Effective Strategies ◽  
Potato Common Scab ◽  
Multiple Species ◽  
Potato Growth

Potato common scab is an important soilborne disease worldwide that can significantly reduce the quality and economic values of potato. The disease is caused by multiple species of Streptomyces, which are not well controlled due to lack of effective strategies. Streptomyces galilaeus has been recently identified as a dominant species causing potato common scab in Inner Mongolia, China. This study was focused on screening and characterizing antagonists for biological control against pathogenic S. galilaeus. Bacterial strain PBSH9 was isolated from a potato tuber. PBSH9 was identified as a Streptomyces sp. on the basis of morphological, physiological, and biochemical characteristics, as well as DNA sequence analysis. PBSH9 inhibited S. galilaeus with a diameter of inhibitory zone of 19.8 mm on agar plates. The extracellular filtrate of PBSH9 also inhibited S. galilaeus growth with a diameter of inhibition zone of 10.0 mm. Furthermore, PBSH9 promoted potato sprouting and emergence. Disease control was up to 81.88% in greenhouse trials, and from 47.64 to 73.97% in 3-year field trials. Among the tested inoculation methods, seed treatment was more effective than soil drenching for PBSH9 application. PBSH9 not only effectively controlled potato common scab but also increased potato growth. Thus, it can be a potential candidate for biocontrol agent.

scholarly journals Edaphic Soil Levels of Mineral Nutrients, pH, Organic Matter, and Cationic Exchange Capacity in the Geocaulosphere Associated with Potato Common Scab

2007 ◽  
Vol 97 (9) ◽  
pp. 1071-1082 ◽  
Author(s):  
George Lazarovits ◽  
Jacquelyn Hill ◽  
Greg Patterson ◽  
Kenneth L. Conn ◽  
Nigel S. Crump
Keyword(s):  
Organic Matter ◽  
Disease Severity ◽  
Common Scab ◽  
Disease Incidence ◽  
Organic Matter Content ◽  
Principal Component ◽  
Exchange Capacity ◽  
Partial Least Square ◽  
High Disease Severity ◽  
The Relationship

In order to determine possible relationships between geocaulosphere soil properties and severity of common scab of potato caused by Streptomyces scabies, soils were collected from representative commercial potato fields in Canada: in Simcoe and Dufferin Counties, Ontario and across Prince Edward Island (PEI) in August 2004. Soils immediately adjacent to tubers were sampled and analyzed for select edaphic factors and for pathogen presence using polymerase chain reaction (PCR) tests with primers that amplify a region of the TxtA gene involved in regulating the biosynthesis of the thaxtomin toxin family. Individual tubers were assessed visually for scab severity. The relationships between soil chemical factors and disease severity were investigated for each region to detect the strongest relationships. Principal component analysis revealed a distinctive clustering of samples with respect to disease severity in PEI but not in Ontario soils. Total and percent saturation of K (%K) were the only factors found associated with high disease severity in soils from both provinces. In PEI soils, pH, Mg, Ca, Cu, and %K, %Mg, %Ca, and %Na were associated with high disease severity, whereas cation exchange capacity (CEC) and Al were correlated with low disease severity soils. In Ontario, high Mn content was strongly correlated with low disease severity soils, whereas %K and organic matter content were correlated with disease severity. Partitioning samples into presence or absence of the TxtA PCR product with corresponding high or low severity showed further significant relationships in the data. There was an excellent correlation between Streptomyces spp. presence as detected by PCR and disease severity in PEI soils; however, the relationship was not as clear in Ontario soils, where many PCR-positive soils had low disease incidence. Principal component and partial least square analysis indicated that disease severity was predicted by soil factors such as organic matter, CEC, pH, Al, %Ca, %Mg, and %K for PEI but not for Ontario soils. The data reveal that the relationship between scab severity and soil chemical components is complex and potentially soil specific.

scholarly journals First Report of Streptomyces stelliscabiei Causing Potato Common Scab in Guizhou Province, China

Plant Disease ◽  
2021 ◽  
Author(s):  
Utpal Handique ◽  
Ruofang Zhang ◽  
Zhxin Zhang ◽  
Zhiwen Feng ◽  
Qinghua Sun ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Phylogenetic Trees ◽  
Common Scab ◽  
Disease Incidence ◽  
Guizhou Province ◽  
Rrna Gene ◽  
Potato Tubers ◽  
First Report ◽  
Potato Common Scab

Potato (Solanum tuberosum L.) common scab can be caused by multiple pathogenic Streptomyces spp. worldwide. Potato tubers (cv. Favorita) with severe pitted common scab symptoms were observed at a small farm (2 hectares) during harvest in Anshun, Guizhou province in early May 2020. The disease incidence was around 10%, and symptomatic samples were collected to isolate the pathogen. Two isolates, ZR-IMU141 and ZR-IMU146 (Accession number MW995958 and MW995959 respectively), showed more than 99% sequence identity to S. stelliscabiei sequences (Accession No. HM018085). Five house-keeping genes for multi-locus sequence analyze (MLSA) of Streptomycetaceae were amplified, sequenced and uploaded to NCBI: atpD (MZ343164 and MZ343165), gyrB (MZ343162 and MZ343163), recA (MZ343166 and MZ343167), rpoB (MZ343168and MZ343169) and trpB (MZ343170 and MZ343171). All the genes show over 98% identity with S. stelliscabiei. Phylogenetic trees of 16S rRNA gene sequence and multi-locus sequence analysis (MLSA) were constructed. The two isolates contain pathogenicity genes txtAB, nec1, and tomA, which was confirmed by PCR. To complete Koch’s postulates, 9 potato seedlings (cv. Favorita, 15 centimeters high), were transferred to new pots and inoculated with spore suspensions of ZR-IMU141 and ZR-IMU146 (104 CFU/ml), or water as a negative control. Two months later, potato tubers inoculated with either ZR-IMU141 or ZR-IMU146 exhibited typical symptoms of potato common scab, such as superficial or deep, raised, pitted, or polygonal lesions like the field symptoms, but the negative controls remained asymptomatic. The pathogens were reisolated from the lesions and confirmed identical to the original isolate by 16s rRNA gene sequences. To our knowledge, this is the first report of S. stelliscabiei causing potato common scab in Guizhou province, China. We believe that this report will draw attention to the study and management of the increased pool of scab pathogens in China.

scholarly journals A Survey of Genetic Variation in Streptomyces Isolates Causing Potato Common Scab in the United States

2006 ◽  
Vol 96 (12) ◽  
pp. 1363-1371 ◽  
Author(s):  
Leslie A. Wanner
Keyword(s):  
United States ◽  
Genetic Variation ◽  
Common Scab ◽  
Disease Incidence ◽  
The United States ◽  
Rrna Gene ◽  
Population Genetic Study ◽  
Variable Regions ◽  
Genus Streptomyces ◽  
Characteristic Features

Common scab is a serious disease of potatoes and other root and tuber crops, affecting crop quality and market value. The disease is caused by gram positive soil bacteria in the genus Streptomyces. Disease incidence and severity vary in different locations and years; this is due in part to variation in the environment (weather) and genetic variation in potato cultivars. Little information is available on the contribution of genetic variation by the pathogen. To examine genetic diversity in different locations within the United States, streptomycetes were isolated from lesions on field-grown potatoes from six states. Isolates were classified into species based on sequence of variable regions in the 16s rRNA gene. The presence of genes associated with the recently described S. turgidiscabies pathogenicity island (PAI) was also determined. About half of the isolates belonged to S. scabies or S. europaeiscabiei based on 16s rDNA sequence, and had characteristic features of the PAI. They were found in all six states, and were pathogenic on potato and radish. The remaining isolates included pathogens and nonpathogens. They were varied in appearance, and represent several species, including one pathogenic species not previously reported. Some pathogenic isolates lacked one or more genes characteristic of the PAI, although all had genes for biosynthesis of the pathogenicity determinant thaxtomin. In this relatively small survey, regional differences in scab-causing streptomycetes were seen. This report furnishes tools and baseline data for population genetic study of scab-causing streptomycetes in the United States.

scholarly journals Effect of Compost Amendments on Disease Severity and Yield of Tomato in Conventional and Organic Production Systems

Plant Disease ◽  
2002 ◽  
Vol 86 (2) ◽  
pp. 156-161 ◽  
Author(s):  
P. A. Abbasi ◽  
J. Al-Dahmani ◽  
F. Sahin ◽  
H. A. J. Hoitink ◽  
S. A. Miller
Keyword(s):  
Disease Severity ◽  
Production Systems ◽  
Disease Incidence ◽  
Organic Production ◽  
Fruit Rot ◽  
High Rate ◽  
Bacterial Spot ◽  
Marketable Yield ◽  
Tomato Production ◽  
Compost Amendments

Field trials were conducted over 2 years to assess the effects of compost amendments on disease development in organic and conventional processing tomato (Lycopersicon esculentum L.) production systems. The incidence of anthracnose fruit rot was reduced in organic tomato plots amended with a high rate of composted cannery wastes compared with the incidence in nonamended control plots in 1998 when disease incidence was high. Marketable yield was increased by 33% in compost-amended organic plots. Plots amended with a high compost rate had more ripe fruit than the nonamended control. The incidence of anthracnose and of total disease on fruit was less on the cultivar OH 8245 than on Peto 696. Total fruit yield of OH 8245 but not Peto 696 in organic plots was increased by amendment with composted cannery wastes. In conventional tomato production, composted yard wastes increased disease severity on foliage both years but reduced bacterial spot incidence on fruit in 1997, when disease pressure was high. The incidence of anthracnose was not affected by composted yard wastes. Marketable and total fruit yields of Peto 696 were not increased in compost-amended conventional plots. The plant activator Actigard reduced foliar disease severity and the incidence of bacterial spot and anthracnose on fruit, while increasing yield of marketable fruit.

scholarly journals Effect of irrigation frequency and fungicide spray on yield and disease infection of onion

1970 ◽  
Vol 34 (3) ◽  
pp. 417-424
Author(s):  
SK Biswas ◽  
MA Razzaque Akanda ◽  
M Rafi Uddin ◽  
PK Sarker
Keyword(s):  
Disease Severity ◽  
Water Use ◽  
Agricultural Research ◽  
Disease Incidence ◽  
Research Station ◽  
Irrigation Frequency ◽  
Yield Attributes ◽  
Irrigation Water Use ◽  
Use Efficiency ◽  
Bulb Yield

A two-year field experiment was conducted at Regional Agricultural Research Station, Jessore during the rabi seasons of 2002-2003 and 2003-2004 to find out the level of disease incidence under different levels of irrigation and fungicide spray on the bulb yield of onion. Four irrigation levels: no irrigation (I1), irrigation at 10 days interval (I2), 20 days interval (I3), and 30 days interval (14) with 4 spray schedules: no spray (F1), one spray at 40 days after transplanting (DAT) (F2), two sprays each at 40 and 55 DAT (F3) and three sprays each at 40, 55, and 70 DAT (F4) were used. Yield and yield attributes varied significantly (p = 0.05) between sprayed and unsprayed, and irrigated and non-irrigated treatments, respectively. Higher yields were obtained with the higher frequencies of irrigation and spray. Application of fungicide reduced the disease severity significantly, while irrigation had no significant effect on disease infection. But there was a decreasing trend of the disease severity with increasing irrigation frequency. The highest bulb yield of onion (12.45 t/ha) was obtained with a total water use of 245 mm in six applications including an effective rainfall of 16 mm and three sprays. The disease severity between sprayed and unsprayed plots ranged from 1.33 to 3.16 for I1, 1.08 to 2.33 for I2 1.16 to 2.83 for I3, and 1.16 to 3.00 for I4, respectively. Key Words: Onion, disease incidence, irrigation, water use efficiency. DOI: 10.3329/bjar.v34i3.3967 Bangladesh J. Agril. Res. 34(3) : 417-424, September 2009

scholarly journals Cotton resistance to ramulose and variability of Colletotrichum gossypii f. sp. cephalosporioides

2006 ◽  
Vol 32 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Jefferson Fernandes do Nascimento ◽  
Laércio Zambolim ◽  
Francisco Xavier Ribeiro do Vale ◽  
Paulo Geraldo Berger ◽  
Paulo Roberto Cecon
Keyword(s):  
Disease Severity ◽  
Disease Incidence ◽  
Disease Index ◽  
Mato Grosso ◽  
Progress Curve ◽  
Commercial Cultivars ◽  
Resistant Group ◽  
The Relationship ◽  
Highly Virulent ◽  
Susceptible Group

Four cultivars and 21 lines of cotton were evaluated for resistance to ramulose (Colletotrichum gossypii f. sp. cephalosporioides) in a field where the disease is endemic. The seeds of each genotype were planted in 5 x 5 m plots with three replications. The lines CNPA 94-101 and 'CNPA Precoce 2'were used as standard susceptible and resistant references, respectively. The disease incidence (DI) was calculated from the proportion of diseased plants in the plot. The disease index (DIn) was calculated from the disease severity using a 1 to 9 scale, and was evaluated at weekly intervals starting 107 days after emergence. The data collected was used to calculate the area under disease progress curve (AUDPC). In general, the DIn increased linearly with time and varied from 20.0 to 57.1 and AUDPC from 567 to 1627 among the genotypes which could be clustered in to two distinct groups. The susceptible group contained two cultivars and nine lines and the resistant group contained one cultivar and 12 lines. The relationship between disease index and evaluation times was linear for the 25 genotypes tested. The line CNPA 94-101, used as susceptible standard, was the most susceptible with an average DI = 83.4, DIn = 57.1 and AUDPC = 1627.7. The line CNPA 96-08 with DI = 37.8, DIn = 20.0 and AUDPC = 567.7 was the most resistant one. Among the commercial cultivars 'IAC 22' was the most susceptible and 'CNPA Precoce 2', used as resistant standard was the most resistant. The variability in virulence of the pathogen was studied by spray inoculating nine genotypes with conidial suspensions (10(5)/mL) of either of the 10 isolates. The disease severity was evaluated 30 days later using a scale of 1 to 5. The virulence of the isolate was expressed by DIn. All the isolates were highly virulent but their virulence avaried for several genotypes and could be clustered in two distinct groups of less and more virulent isolates. The isolate MTRM 14 from Mato Grosso was the least virulent while Minas Gerais was the most virulent, with DIn of 6.36 and 46.47, respectively. In this experiment the line HR 102 and the cultivar 'Antares' were the most resistant ones with DIns of 18.32 and 19.14, respectively.

Sign in / Sign up

Export Citation Format

Share Document